Alpha presets for chart layers

Returns a named numeric vector of alpha values for common chart roles. Use them when setting alpha = in ggplot2::geom_*() or plotly traces. Alpha lowers the effective contrast a viewer sees, so verify the composited contrast with a11y_check_palette() when the choice matters.

Usage

a11y_alpha_presets()

Value

Named numeric vector with elements raw_points, overlay_point, labels, fill, ci_ribbon, ci_band.

Examples

a11y_alpha_presets()
#>    raw_points overlay_point        labels          fill     ci_ribbon 
#>          0.40          0.60          0.70          0.90          0.10 
#>       ci_band 
#>          0.15 
a11y_alpha_presets()[["overlay_point"]]
#> [1] 0.6